Back to the beginning

deacon · Jul 30, 2009

Who would have thunk it. When I built my very first power bike it was an Ebike. I had my neighbor weld a drive onto a scooter motor and hooked it to the rear of an old huffy. It wasn't fast and the range wasn't much but it worked. Then I got caught up in a BETTER idea.

Yesterday, I decided that since I have learned so much I wanted to do it again. Just as simple as before but with an improved knowledge (I hope) of what works best. I have one pusher bike that runs really well. I need to retest it, since I over powered the controller, to make sure it still works.

Then I am going to build a direct friction drive. Pushers and gasoline motors are complicated. A friction drive is simple and I think I want to simplify things this time. I am still looking for that bike to ride to the store for a loaf of bread and a jar of peanut butter.

deacon · Jul 31, 2009

I got the motor onto a bike frame I had but I lost the front brakes. I had to mount it on the front. I got to ride it this afternoon and it looks to be fast for an ebike. I don't have decent brakes so i only rode it up and down the drive. I am going to take it off the 26" bike and put it on a 20" one. That is after a trip to the thrift store to buy it. The mountain bike I have just won't do. I will probably go with a kids bike so I can mount the drive over the rear wheel.

Since this uses a scooter wheel to turn the bike wheel, it will run on a knobby tire but I'm hoping I can find a not so knobby one laying about.

deacon · Aug 1, 2009

strange looking beast.

I had a blowout on my first ride. I got about 3/4 miles down the test track and it went pop. Scared me a bit.

deacon · Aug 1, 2009

I should be able to compare my last two bikes since I used exactly the same motor on both. However I can't. Here is why. When I used the stock scooter wheel and sprocket as a pusher wheel the results were close to those of the this friction drive with the stock scooter wheel and sprocket. I find that it has a lot to do with modifications and I haven't started to modify this friction drive yet.

The pusher mods were, a smaller sprocket welded to a 16" bike coaster wheel. That was the most efficient performance wise. I pretty much cut the size of the sprocket in half, then added 25% more wheel radius.

Looks like I need to do something like that to the friction drive. It is going to be hard since the wheel is pretty much max now. I think I will look around to see what I can find to be modified.

deacon · Aug 3, 2009

I got the bike set up better thank before. It still has a stock motor and a stock scooter wheel set up as a friction drive and it works pretty well now. About like an average ride. top speed is about ten miles an hour I would guess. Minimum equipment. I have no controller but the power consumption seems about the same as with one.

I have a larger sprocket on the way. I was going to make a new drive wheel with it but I might just put it on the motor and use it that way. I haven't made a final decision yet. I might just experiment.

deacon · Aug 3, 2009

I took the bike and trailer out on a real world ride to the park. It worked very well. It is slow but that's okay. I'm not really out in traffic with it on that run. I'm toying with the idea of making a friction drive from the fast pusher I have.

I'll be giving that some thought while I wait for the sprocket, which I will use on the home made drive wheel. That is if I go that route.

The evaluation of the 350 watt motor with no controller on a friction drive using the rear scooter wheel as a drive is that it has lots of torgue. It is slow but it climbs small hills at almost the same speed as it runs on the flat. It probably is doing 10 to 12 mph which is better than I could do on a pedal bike. It will also help me start from a dead stop without blowing a fuse. It does have some good points.

The worst thing is that I put it one a bike with no suspension at all. It is one rough riding sob for sure. The twenty inch sissy frame is really too light weight I think and the pedal gear ration is all very low gear.It probably could use a larger front chain ring. I might take a look at that. I'm pretty sure I have one laying about.

deacon · Aug 4, 2009

I rode the friction drive to the park today. I built it primarily for that purpose. An easy to ride inexpensive more or less disposable bike. It is low powered and slow compared to my 500 watt pusher bike, but it is a pleasant ride. The bike does not require that I maintain a high speed at all. As a matter of fact it will just skip over the wheel when I start or when if I get too slow going uphill. I can pedal at a very moderate rate to prevent it skipping. So yes I am slow but I don't mind at all. By the way this bike has great torque. It also has better range just because it is so slow that it will coast for a long way before I have to kick the power back on when it is going on the flat.

I have started to build my own drive wheel. If I am successful, I might just put it on the fast pusher so that I don't have to mess up this one. What in effect I am building is a mini pusher that ride on top of the bikes wheel. It is a little different but not much. The one I have now is no different at all. By the what

motorbiker · Aug 5, 2009

Hi, friction drive trips me out. If the bicycle tire is made smaller and the roller stays the same the bicycle tire will turn faster but the bike will go the same speed because the smaller tire has to spin faster to make the bike go the same speed as the larger size tire ? Right ?

How many teeth are on the sprockets and what are the real time tire sizes ?

What size roller would need to be on the motor shaft if the roller on the motor shaft was right on the tire ?

With my weed wacker 33cc motor it needs to be about 7/8" diameter for me. Thanks

deacon · Aug 5, 2009

Bike tire size is immaterial. If you turn the tire one inch the bike moves one inch no matter what size the tire on the bike. Its all about the drive wheel and the motor. I usually use a direct drive on my friction setup but not this time. This time I am using the scooter motor as it was on the scooter. I just moved the whole setup to the top of the bike wheel.

This one has an 11tooth sprocket on the motor. Then it has a 44tooth sprocket on a 8 inch scooter wheel. It will push the bike along faster than I could pedal it uphill. What it really does is to make it possible for me to climb a moderate sized incline as if I was pedaling on a flat.

The pusher motor does better because it is a bigger drive wheel and a stronger motor. This set up is the smallest thing I have at the moment.

I am currently trying to assemble a DIY drive wheel. It is a six inch lawn mower wheel on a 3/8" axle. It will have an 18 tooth sprocket in the drive and an 11tooth sprocket on the motor. It will turn the wheel faster but the wheel has a smaller diameter. It should change the overall speed of the bike, but it most likely will reduce the torque. For that reason I have to try it before I get married to it. I love the torque of the bike the way it is now.

deacon · Aug 6, 2009

On the diy drive wheel setup. My bearings came. I had to mount them to the drive wheel frame since I couldn't mount them to the wheel. Unlike a bike the axle is going to turn along with the wheel.

Holding the bearing against the frame is the trick it seems. I drilled a hole in the frame just a little larger then the 1/2 inch inside ring of the bearing. The bearing bore is 3/8 so I am using a 3/8 all thread rod as an axle.

I have attached a lawn mower 6" wheel to the axle with nuts and lock washers. I have an 18 tooth 1 5/8" sprocket coming. I will attach it with nuts and lock washers as well. If that won't hold then I'll just weld it.

I drilled out a couple of 5/16 nuts and ground off the corners to make spacers for the inside of the bearings. I drilled a hole in a piece of wood I had which is the same size as the bearing thickness. I used a 5/8 cut washer at the rear of the bearing a keep it from moving. A standard 3/8 nut will turn inside the washer so it is a good fit.

I think this thing will work but I don't know for sure. I'll let you know in the next day or so.

If this one works out okay I might just build another one for my smaller bike. I like the engine on it which is also friction now. I am scraping out all my pusher motors. They were fun and worked very well but it's time to try something new. The friction drives are the something new, even though I have worked with them before. I have not worked with them this way. Before I used direct drives attached to the motor.

motorbiker · Aug 7, 2009

Interesting thread. I like the lawnmower wheel idea. I am going to have to find an electric scooter motor.

deacon · Aug 7, 2009

For some reason known only to god and the usps, my sprocket went back to California. Why I have no idea. It should be back here again middle of the week and I can try to make the wheel work. In the meantime the one with the scooter rear wheel is humming right along. I like it better everyday. Except for about an hour today when the rear bike wheel tossed it's sprocket for some reason. The reason is that the retainer came off on it's own accord. I went up to the thrift shop and bought another junker for four bucks. I got a front wheel, a back wheel, and a set of training wheels for my grandson's bike. Not to mention the chain. Some junker will most likely get the rest.

Motorbiker I wouldn't get a scooter motor smaller then 350 watts. It seems to be a really good size for one of these little bikes. For me the 20" kids bike makes the best platform.

deacon · Aug 8, 2009

I checked online and the expected delivery date for my sprocket is now next friday. Since I have nothing to do till then, I went savaging in my old parts box. I found a small 11 tooth sprocket. That would make it a one to one ratio so I put together a drive using it. The down side is that the bore is 5/16 not 3/8 like the one on order. I had a couple of skate board bearings left over from a previous attempt at this project. So I put together a frame using them the 1/1 sprocket and an old drive wheel of under three inches in diameter. That would still be at least a 2/1 ratio. I also gorilla glued a piece of sandpaper to the smooth drive.

This sounds foolish I know but it is exactly the same design as the 3/8 drive. It will give me a chance to work out some of the bugs before I build the bigger one. Tomorrow is a 'lot of family' day, so I might get a little done but I'm not counting on it. Right now the question to be answered is where to mount the motor on the drive unit.

This particular type motor mount I have been using hangs if off the drive axle. On this one there is no reason for that to be the case. On the mount as is, it hangs to the side of the actual drive unit. I would kind of like to mount it so that the weight is over the tire on this build. I am hoping to be able to do that. Only time will tell, but there is hope since the welding has taken a quantum leap in quality.

deacon · Aug 9, 2009

I finally got the pint sized version of my diy drive completed. Well once I weld the hinge on it is complete. Of course then I have to mount it. I never could get the skateboard bearings to hold in place on the frame so I made some steel bushings for the test drive. if I have trouble with the real one and the bearings I got from ebay, I plan to make brass bushings for the frame. If after all my testing the bike doesn't do really well, then I will buy the rear wheel from a scooter and just made a more powerful version of the bike I have now. I like it just fine.

I am more or less playing around now.

deacon · Aug 10, 2009

I had a huge failure today with the diy drive I was building but I stayed with it and have the beginnings of an inexpensive drive we can all build. I am using skateboard bearings on the small test model and so far after a few missteps it look promising. If the drive works with these bearings there is no reason I can't build one using a kick scooter wheel as the drive and the bearings from it as well.

On ebay i could get the makings of four drive wheels and bearing for under twenty bucks. The kick scooter wheel is 100mm almost four inches. It uses a 5/16 axle probably. If so then an 11tooth sprocket will work on it. I have one on the one I am test building now. That gives the motor a one to one ratio then a 4to1 or so on the drive wheel. That would make the wheel turning at about 700 rpm more or less. I have no idea what speed that would be but probably at least 10 to 15 mph.

deacon · Aug 11, 2009

I tested the test drive I built from scratch. It actually works but there is a lot of drag or something. The bike runs way too slowly. I decided to put that part of the project on hold. I ordered another scooter wheel to just sit on top of the rear wheel of a bike. That is the easiest friction drive I have ever seen. It also works very well.

I have decided to switch my bikes from the pusher back to friction drive. It is a heck of a lot easier to keep adjusted. Also easier to move in and out of the shop. I don't really need the extra speed of the pusher to be honest.

deacon · Aug 11, 2009

I couldn't stand it, I had to go back and try to fix that lawn mower wheel drive. It isn't quite straight but I have it mounted and I'm going to give it a shot. It has the small sprocket, a one to one with the engine, so it should be interesting if it doesn't fly apart.

It's just an experiment since I have a real scooter wheel coming which I can use as a drive for the friction drive. It is pretty big, eight inches actually, so it looks funny. But heck who cares, I guess.

I am already using one of those so I know it works. I think I am going back to plan "A" and mount the 18 tooth sprocket on the motor. That should increase the output by about 50 percent I guess. I just can't leave well enough alone.

deacon · Aug 12, 2009

I think i whipped that lawnmower wheel drive. I have it on the bike but of course it's raining. I think I have the bearings so that they won't bind. I have the wheel itself true now. That just took a night to think on the problem. I tried it using a couple of 3/8 inch nuts that look like acorns. The nylon keeper on top slips right into the wheel's 1/2" opening then when I tightened it the nut just pushed right in evenly. I used on on the other end as well but it didn't push in it just got tight. How long that will hold is anyone's guess. First clear day or if the roads dry off I will give it a try.

deacon · Aug 12, 2009

bear in mind I haven't tested this yet but here is how it looks ready for testing....

[/IMG]

deacon · Aug 12, 2009

By the way I am still learning as I go... I discovered that if you cut the bearing cups off an old bike front wheel they will work as holders for sealed bearing. One can weld those holders to the frame. I wish I had figured that out sooner.

Back to the beginning

minor bike philosopher

minor bike philosopher

minor bike philosopher

minor bike philosopher

minor bike philosopher

minor bike philosopher

minor bike philosopher

New Member

minor bike philosopher

minor bike philosopher

New Member

minor bike philosopher

minor bike philosopher

minor bike philosopher

minor bike philosopher

minor bike philosopher

minor bike philosopher

minor bike philosopher

minor bike philosopher

minor bike philosopher